One-way nut and bolt

ABSTRACT

The bolt, in the one-way nut and bolt combination, includes a head, a stem, and bolt thread on said stern. A longitudinal channel is defined on the stem by a plurality of aligned notches extending through the crests of the threads. Each notch is defined by a radially aligned surface and an angularly displaced surface. The nut has a threaded bore that is complimentary to the bolt thread and includes at least one longitudinal cut-out. The nut further includes a compressible tine extending into the cut-out. The compressible tine has a body portion and a substantially radially aligned distal end portion. The distal end portion of the tine and the cut-out defines a narrow mouth leading to a wider throat deeper in the cut-out. The nut thread and the bolt thread cooperatively permit a user to translate the nut along the bolt threads by means of one-way rotation. The tine is alternately flexed inboard into the cut-out, by the bolt threads, and then released when the tine is disposed in the longitudinal channel. The longitudinal channel and respective notches forming the channel prevent counter-rotational movement of the nut on the bolt when the distal end of the tines abuts the radially aligned surface of the notches.

The present invention relates to a self-locking nut and bolt assemblyand, more particularly, to a self-locking nut and bolt assembly in whichthe nut can be easily threaded onto the bolt in one direction, but whichcannot be counter-rotated.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 307,722 to Klemroth discloses a nut lock wherein the nutincludes a projection or prong at its end. The bolt includes alongitudinal groove through the crest of the bolt threads. When the nuthas been screwed onto the bolt, to a desired position, and the prong isaligned with the groove, the remote end of the prong can be punched ordriven into the groove thereby firmly locking the nut on the bolt.

U.S. Pat. No. 2,484,645 to Baumle discloses a screw fastener havinglongitudinal ridges that partially block the inner spaces defined by theroot of the bolt threads. These longitudinal ridges coact with thelongitudinal ridges found in female thread rolled dies.

U.S. Pat. No. 2,232,336 to Meersteiner discloses a fastening screwhaving longitudinal channels extending through the bolt thread crest androots.

U.S. Pat. No. 4,024,899 to Stewart discloses resilient tines formed onthe apex or peak portions of the threads on both the nut and bolt. Theseresilient tines coact with slightly dished or concave recesses incorresponding tines.

U.S. Pat. No. 591,062 to Smith discloses a bolt having a raised,threaded portion with a spur or lug. The spur or lug has a shoulder atone side and a beveled face at the other which locks a nut againstcounter-rotation.

U.S. Pat. No. 4,168,731 to Tabor discloses a nut having an internallythreaded cylindrical inner wall portion joined at one end by aconnecting portion to an outer wall portion. The inner and outer wailsare separated by an annular volume.

OBJECTS OF THE INVENTION

It is an object of the present invention to provide a one-way nut andbolt combination.

It is another object of the present invention to provide a one-way nutand bolt combustion which locks the out and bolt at predefinedpositions, thereby eliminating the possibility that vibration may loosenthe nut and bolt.

It is a further object of the present invention to provide a nut thatcan readily be removed, by a user, from the bolt.

It is yet another object of the present invention to provide a one-waynut and bolt combination that does not require the use of any specialtools to correctly install the nut on the bolt.

It is a further object of the present invention to provide a one-way nutand bolt combination which automatically locks into place uponcounter-rotational movement of the nut without additional actions ormechanical adjustments to secure the lock between the nut and the bolt.

It is still another object of the present invention to provide a one-waynut and bolt combination in which if the nut is put on the boltbackwards, the nut will not lock and the nut and bolt combination can beused as an ordinary mu and bolt combination.

SUMMARY OF THE INVENTION

The bolt in the one-way nut and bolt combination, includes a head, astem, and bolt tread on said stem. A longitudinal channel is defined onthe stem by a plurality of aligned notches extending through the crestsof the threads. Each notch is defined by a radially aligned surface andan angularly displaced surface. The nut has a threaded bore that iscomplimentary to the bolt thread and includes at least one longitudinalcut-out. The nut further includes a compressible tine extending into thecut-out. The compressible tine has a body portion and a substantiallyradially aligned distal end portion. The distal end portion of the tineand the cut-out defines a narrow mouth leading to a wider throat deeperin the cut-out. The nut thread and the bolt thread cooperatively topermit a user to translate the nut along the bolt threads by means ofone-way rotation. The tine is alternately flexed inboard into thecut-out, by the bolt threads, and then released when the tine isdisposed in the longitudinal channel. The longitudinal channel andrespective notches forming the channel prevent counter-rotationalmovement of the nut on the bolt when the distal end of the tines abutsthe radially aligned surface of the notches.

BRIEF DESCRIPTION OF THE DRAWINGS

Further objects and advantages of the present invention can be found inthe detailed description of the preferred embodiments when taken inconjunction with the accompanying drawings in which:

FIG. 1 illustrates a side view of the one-way nut and bolt of thepresent invention;

FIG. 2 illustrates a bottom cross-sectional view of the bolt of thepresent invention;

FIG. 3 illustrates a partial, cross-sectional view of the bolt from theperspective of section line a'--a" in FIG. 2;

FIG. 4 depicts a partial, cross-sectional view of the bolt andparticularly showing a notch on a bolt thread in accordance with theprinciples of the present invention;

FIG. 5 depicts a top view of the nut of the present invention;

FIG. 6 shows a bottom view of the nut of the present invention;

FIG. 6A illustrates a perspective view of the nut of the presentinvention;

FIG. 7 depicts a bottom view of the present one-way nut and boltcombination when the tines are compressed inboard; and

FIG. 8 shows the one-way nut and bolt combination when the tines areextended or in a locked position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention relates to a nut and bolt combination that allowsone-way rotational movement.

FIG. 1 illustrates one-way nut and bolt 10 including bolt 20 and nut 40.Bolt 20 includes head 22, stem 24, and bolt 26. FIG. 1 also showschannel 28.

Referring to FIGS. 2, 3 and 4, bolt 20 includes bolt head 22, stem 24,bolt thread 26, longitudinal channel 28, radially aligned channelsurface 28', angularly displaced channel surface 28", notch 30 (definedby surfaces 28' and 28"), bolt crest 32, bolt trough 34, and triangularlocking surface 38.

Referring particularly to FIGS. 1 and 2, bolt 20 has a bolt thread 26thereon. Thread 26 is defined by a bolt crest 32 and a bolt trough 34.Longitudinal channel 28 extends through bolt thread 26 due to thelongitudinal alignment of the notices in each bolt thread. Referringparticularly to FIG. 2, radially aligned surface 28' and angularlydisplaced surface 28" converge to form a notch 30 at each threadcrossing. FIG. 1 illustrates a plurality of aligned notches 30 whichdefine longitudinal channel 28.

FIGS. 5, 6 and 6A illustrate nut 40 having bore 42, nut thread 43,longitudinal cut-out 44, straight wall portion 46, arcuate wall portion48, mouth opening 45, throat opening 47, and compressible tine 50disposed in the cut-out. Compressible tine 50 includes backside surface49, straight body proximal portion 52, arcuate distal portion 54 anddistal end surface 56.

FIGS. 1, 6, 7 and 8 illustrate bolt tread 26 and nut thread 43cooperatively permitting a user to rotate nut 40 one way one bolt thread26, thereby permitting generally one way translational movement towardshead 22 in FIG. 1. During the translation of nut 40 along bolt threads26, tines 50 are alternately compressed inboard into cut-out 44 bycontacting bolt threads 26, and then released to expand into the boltchannel when distal end 56, of tine 50, is disposed in longitudinalcentral axis 28. Tine 50 and triangular locking surface 38, oflongitudinal channel 28, thereby cooperatively prevent rotation of nut40 in direction L.

Referring particularly now to FIG. 7, it can be seen that a userdesiring to translate nut 40 toward bolt head 22 may do so by rotatingnut 40 in direction T. When tines 50 are compressed by bolt crest 32,due to contact between end 56 and crest 32, the tine 50 is flexedoutboard, with respect to longitudinal central axis 60, best seen inFIGS. 1 and 7. When tine 50 flexes outboard backside 49, of tine 50, ismore closely disposed toward straight wall portion 46 and arcuate wallportion 48 of cut-out 44. As described above, tine 50 includes straightbody proximal portion 52, arcuate distal portion 54, distal end 56 andbackside 49. The straight body 52 and large opens thread 47 permitmultiple flexible movements of the tine in the cut-out.

Referring now to FIG. 8, when nut 40 is rotated such that distal end 56of tine 50 is disposed in longitudinal channel 28, counter-rotationalmovement, in direction L, cannot occur. End 56 abuts radial surface 28'and triangular locking surface 38 in FIG. 3. When nut 40 is rotated suchthat distal end 56, of tine 50, is received by notch 30, andcorespondently disposed in longitudinal channel 28, tine 50 is releasedfrom compression. As described above, longitudinal channel 28 is definedby radially aligned surface 28' and angularly displaced surface 28". InFIGS. 3 and 8, triangular locking surface 38 of radially aligned surface28 abuts distal end 56 and prevents rotation of nut 40 in direction Lwhen tine 50 is disposed in longitudinal 28. A user desiring to continueto rotate nut 40 in direction T may do so and tine 50 will again becompressed when distal end 56 contacts bolt crest 32.

Referring now to FIGS. 4, 7 and 8, mouth 45 is defined by distal end 56and arcuate wall portion 48. Throat 47 is defined by backside 49 of tine50 and the distal end segment of arcuate wall portion 48 of cut-out 44.In FIGS. 4, 7 and 8, mouth 45 is narrower an and leads to throat 47.When tine 50 is compressed by bolt crest 32, both mouth 45 and throat 47narrow. However, mouth 45 continues to be wider than throat 47.

The one-way nut and bolt combination is made from injected or moldedplastic. The tines and the cut-outs in the nut extended longitudinallyon an inboard surface through the threaded nut bore. In the preferredembodiment, each cut-out extends longitudinally through the entire nut.Similarly, a single tine extends throughout the longitudinal cut-out.Alternatively, multiple tines could be dispose, in an aligned manner, ineach cut-out. The claims appended hereto are meant to cover thisconcept.

To remove the locked nut from the bolt, a tool having a single prong foreach cut-out is inserted into the cut-out at a position radially inboardthe body of the tine. This tool then compresses the tine (or tines ifmultiple, circumferentially spaced cut-out and tine configurations areutilized) and the compressed tine is radially moved outboard or awayfrom the triangular locking surface at each bolt thread. The nut ismoved or is translated away from the bolt head by substantiallysimultaneous counter-rotation of the nut, the outwardly disposed andcompressed tine and the tool. In the illustrated embodiment, a threeprong removal tool is utilized. The three prongs are joined together andcircumferentially spaced apart the appropriate distance by a head plateor grid.

Another technique to remove the nut from the bolt involves theapplication of a high degree of reverse torque which causes the tine ortines to repeatedly "pop-out" of the notch over the triangular lockingsurface. Experimentally, the nut has been removed up to 10 times withoutsignificant deterioration.

One-way nut and bolt 10 can be made of a variety of materials. In thepreferred embodiment, one-way nut and bolt 10 is cast from long glassfiber nylon. One-way nut and bolt 10 can be produced utilizing a numberof casting methods. In the preferred embodiment, a multi-cavity singleinjection mold, requiring no additional manufacturing steps, is used toproduce one-way nut and bolt 10.

The claims appended hereto are meant to cover modifications and changeswithin the spirit and scope of the present invention.

I claim:
 1. A one way nut and bolt comprising:a bolt having a bolt headand a bolt read on a stem depending from said head, and bolt having alongitudinal channel extending through said threads and defined by aradially aligned surface and an angularly displaced surface convergingto form a notch at each thread crossing, said longitudinal channelformed by a plurality of aligned notches, said threads defined by acrest and a trough; a nut having a bore therethrough with an interiornut thread thereon that is complimentary to said bolt thread, said nuthaving a longitudinal interior cut-out therethrough, said cut-outdefined by straight and arcuate wall portions; a compressible tineextending into said cut-out, said tine having a straight body proximalportion, an arcuate distal portion and a distal end, said distal end ofsaid tine and said arcuate portion of said cut-out defining a narrowmouth leading to a throat, said throat defined by a backside of saidtine and an inwardly disposed segment of said arcuate wall of saidcut-out, said throat being larger than said mouth; whereby said nutthread and said bolt thread cooperatively permit translation of said nutalong said bolt threads by one way rotation of said nut during whichsaid tine is alternately compressed by contact with said rests and thenreleased when disposed in said longitudinal channel, said longitudinalchannel preventing counter-rotational movement of said nut when saidtine is disposed in said longitudinal channel and said distal end ofsaid tine abuts said radially aligned surface of said notch at each boltthread crossing.
 2. A one way nut and bolt as recited in claim 1,wherein said bolt further includes a longitudinal central axis and saidstraight body proximal portion of said tine is outwardly disposed fromsaid crest of said bolt threads relative to said longitudinal centralaxis of said bolt.
 3. A one way nut and bolt as recited in claim 2,wherein said radially aligned surface includes a locking triangularsurface that cooperates with said distal end of said tine.
 4. A one waynut and bolt as recited in claim 3, wherein said bolt thread has apredetermined thread depth and said longitudinal channel has a channeldepth that exceeds said thread depth.
 5. A one way nut and bolt asrecited in claim 1, wherein said nut further comprises a plurality oftines circumferentially spaced around said nut bore.
 6. A one way nutand bolt as recited in claim 5, wherein said plurality of tines areequally and circumferentially spaced around said nut bore.
 7. A one waynut and bolt as recited in claim 6, wherein said bolt nut comprises aplurality of longitudinal channels circumferentially spaced around saidbolt stem.
 8. A one way nut and bolt as recited in claim 7, wherein saidplurality of longitudinal channels are equally and circumferentiallyspaced around said bolt stem.
 9. A one way nut and bolt as recited inclaim 8, wherein an end of said distal ends of said tines arelongitudinally disposed in a plane parallel to the plane defined by saidradially aligned surface.
 10. A one way nut and bolt as recited in claim9, wherein said cut-out extends through the longitudinal extent of saidnut bore.
 11. A one way nut and bolt as recited in clam 10, wherein saidtine longitudinally extends through said longitudinally cut-out.
 12. Aone way nut and bolt as recited in claim 1, wherein said tine andnotches form multiple locking surfaces throughout said nut bore.
 13. Aone way nut and bolt as recited in claim 12, wherein said multiplelocking surfaces are triangularly shaped and formed by said longitudinalchannel and said notch at said radially aligned surface.
 14. A one waynut and bolt .Iadd.combination, said bolt .Iaddend.having a head, a stemand a bolt thread on said stem, said bolt having a longitudinal channeldefined by a plurality of aligned notches, each notch defined by aradially aligned surface and an angularly displaced surface on each boltthread;a nut having a threaded bore that is complimentary to said boltthread said nut bore having at least one longitudinal cut-out; acompressible tine extending into said cut-out having a body portion andsubstantially radially aligned distal end portion, said distal endportion of said tine defining a narrow mouth leading to a wide throat insaid cut-out, said mouth-opening to said nut bore; whereby said nutthread and said bolt thread cooperatively permit translation of said nutalong said bolt threads by one-way rotation, while said tine isalternately flexed inboard into said cut-out by said bolt threads andreleased when said tine is disposed in said longitudinal channel, saidlongitudinal channel and respective notches preventingcounter-rotational movement of said nut and bolt when said end of saidtine abuts said radially aligned surface of said notches.
 15. A one waynut and bolt as recited in claim 14, wherein said throat is narrowedwhen said tine is flexed inboard into said cut-out. .Iadd.
 16. A one waynut and bolt combination comprising a bolt having a head, a stem and abolt thread on said stem, said bolt having a plurality of indentationson each bolt thread aligned to form a locking channel on said stem;a nuthaving a threaded bore that is complimentary to said bolt thread, saidnut bore having at least one longitudinal cut-out; a compressible tineextending into said cut-out having a body portion and substantiallyradially aligned distal end portion, said distal end portion of saidtine defining a narrow mouth leading to a wider throat in said cut-out,said mouth opening to said nut bore; whereby said nut thread and saidbolt thread cooperatively permit translation of said nut along said boltthreads by one-way rotation, while said tine is alternately flexedinboard into said cut-out by said bolt threads and released when saidtine is disposed in said locking channel, said locking channel andrespective plurality of indentations preventing counter-rotationalmovement of said nut and bolt when said end of said tine is positionedin one of said plurality of indentations..Iaddend..Iadd.17. A one waynut and bolt as recited in claim 16, wherein said throat is narrowedwhen said tine is flexed inboard into said cut-out..Iaddend..Iadd.18. Aone way nut and bolt as recited in claim 16 wherein said indentationsare notches on each said bolt thread..Iaddend..Iadd.19. A one way nutand bolt as recited in claim 18 wherein each said notch extends throughsaid respective bolt thread..Iaddend..Iadd.20. A one way nut and bolt asrecited in claim 16 wherein said indentations are longitudinally alignedon said stem..Iaddend..Iadd.21. A one way nut in combination with a bolthaving a head, a stem and a bolt thread on said stem, said bolt having alocking channel defined by a plurality of aligned notches on each boltthread, said nut comprising:a nut body having a threaded bore that iscomplimentary to said bolt thread, said nut bore having at least onelongitudinal cut-out; a compressible tine extending into said cut-outhaving a body portion and substantially radially aligned distal endportion, said distal end portion of said tine defining a narrow mouthleading to a wider throat in said cut-out, said mouth opening to saidnut bore; whereby said nut thread and said bolt thread cooperativelypermit translation of said nut along said bolt threads by one-wayrotation, while said tine is alternately flexed inboard into saidcut-out by said bolt threads and released when said tine is disposed insaid locking channel said locking channel and respective notchespreventing counter-rotational movement of said nut on said bolt whensaid end of said tine is disposed within at least one of said pluralityof notches..Iaddend..Iadd.22. A one way nut and bolt as recited in claim21, wherein said throat is narrowed when said tine is flexed inboardinto said cut-out..Iaddend..Iadd.23. A one way nut and bolt as recitedin claim 21 wherein each said notch extends through said respective boltthread..Iaddend..Iadd.24. A one way nut and bolt as recited in claim 23wherein said notches are longitudinally aligned on said stem..Iaddend.